Valuable thread... thanks!
I'll add this tool that I found that appears to be "official":
www.gov.cn/govdata/html5/2018/visafreetransit/pc/index.html]72/144-Hour Visa-Free Transit in China[/url] There are some holes in it. Hong Kong and Macau are not listed as "from" or "to" options.
Some people have claimed that they enter TWOV Guangdong via train, but that seems incorrect?. Everything I've read says there are only 3 entry ports: Guangzhou Baiyun International Airport, Shenzhen Bao'an International Airport, Jieyang Chaoshan International Airport. Entry via train, ferry, and car is not applicable, right?
I've read there are 32 (or is it 38?) exit port. How is it that Shenzhen Bei and the train to Hong Kong is not one? Will that work now, and the internet pages have not caught up? (Really a pity that there is no official government website with the rules and info... all I've found have been travel agency and tour pages.)
I'll be in HK, and trying to plan backup in case my new VISA does not make it through the clogged system here in the USA in time. It looks like the only choice is to fly HKG -> CAN, and then maybe train to Macau, and ferry back to Hong Kong. Is that return trip as grueling as I imagine? Not so much the actual travel, but that would be a few times through customs, right?
Thanks for all the help here... especially the same few guys that seem to be answering everything. Your service is appreciated. :-)